Discussion in 'Primary' started by Loopyloz, Feb 25, 2012.

1. ### Loopyloz

I am still getting to grips with the year 2 maths. I am trying to plan for the objective 'use practical and informal written methods to add and subtract two-digit numbers'.

How should this be taught? should children be doing it in columns and adding the tens and units??

2. ### Loopyloz

I am still getting to grips with the year 2 maths. I am trying to plan for the objective 'use practical and informal written methods to add and subtract two-digit numbers'.

How should this be taught? should children be doing it in columns and adding the tens and units??

3. ### katman

No, that's standard written method. Numberlines, dienes , partitioning and recombining are all appropriate methods.

http://www.auriol.surrey.sch.uk/Progression%20in%20Calculations%20for%20Parents.pdf

I found this fab document to show someone recently.Page 6 is about where I'd expect your lot to be working for addition. Please don't go straight to standard written method. I teach Year 3 and my more able kids might look at standard written method for addition and subtraction later in the year but we are still very much about number lines and partitioning with informal recording for the moment. You need to be sure that your pupils have a really clear understanding of place value and what is going on in addition and subtraction before they venture anywhere near standard written method.

HTH

4. ### cally1980Established commenter

Checkout your school's calculation policy, they might prescribe the methods they want you to teach.

5. ### clawthorpegirlNew commenter

I start by checking children can navigate around a number line and hundred square and use these first. They need to be able to partition so they can add / subtract the tens first, followed by the units. Depending on class we also look at bridging through 10.
Then we move on to drawing and using an empty number line so they have a method they can use without needing a hundred square or-pre drawn number line. The less able children will need to jump on or back individual tens first, followed by individual units. More able may be able to do less, bigger jumps.

6. ### butterbeer

Children at this level are usually partitioning to add and subract, but generally horizontally, rather than the column method, as they must be absolutely secure about what they are doing with the numbers when they are adding and subtracting. So
42 + 35 =
40 + 30 = 70
2 + 5 = 7
70 + 7 = 77
42+ 35 = 77
(they might not need to do all these steps separately). They don't need to write it formally like this all the time, as there are lots of other ways of doing it. They then move onto calculations that take the units over 10 etc and look at exchange in addition and subtraction which we teach using lots of practical apparatus. To give you an idea of where we are, most of my lower Year 2s have got exchange with adding, but are not secure yet on exchange with subtraction. My more able are good with this and are doing more open ended investigations.
They will also be using their knowledge of number bonds, halves and doubles, adding to the next multiple of ten, crossing the tens etc to become confident at adding and subtracting 2 digit numbers. it is crucial for them to see the patterns and use and apply what they know. When they are really secure on their number bonds to 10, 20 and 100 and their halves and doubles (and spot near doubles ec) they can use this is so many ways to help with the calculations. I would be focussing on these skils and then seeing if they can apply them with some practical problem solving. We encourage them to draw pictures etc to help them work through problems and there are lots of informal ways of recording they could be having a go with.

7. ### Loopyloz

thanks to everyones responses much appreciated and much clearer now. If i want them to record in their books sing up could i get them to record how you have wrote it above so i can see if they have understood to partition the tens and units??

8. ### Loopyloz

thanks for your help and that document you recommended is brill. Thanks

9. ### butterbeer

Hi Loopyloz
Yes at some stage I would get them to record the calculations so I could see they understand the oprocess, but as others have said, making sure they have a good grasp of the basics and understand place value etc is really important. As someone mentioned, there should be a calculation policy at school for you to refer to.

10. ### Loopyloz

Thanks sing up and thanks to everyone else for there help and advice